The present invention relates generally to an apparatus for producing a fiber web.
More particularly, the invention relates to a carding apparatus for withdrawing the fiber web in a divided manner, so that simultaneously at least two slivers may be formed by juxtapositioned sliver trumpets. In a known carding apparatus the web is divided as it issues from the squeezing rollers. Each of the two thus-obtained web parts is then admitted into a separate trumpet.
Thus, more particularly, it is known to separate the fiber material in the carding apparatus by means of a particular arrangement of the clothing of the various roller or cylinder components of the card such as the feed roller, the licker-in, the carding cylinder, the doffer or the web take-off roller. Accordingly, in order to effect a longitudinal division of the fiber web, it has been known to omit several rows of clothing teeth or to render ineffective such rows of clothing teeth by placing an adhesive substance over the tooth rows or by filling the spaces between such rows with metal or the like. U.S. Pat. No. 1,189,740 discloses a carding machine in which the fiber material (web) is divided by providing a covering strip over a narrow circumferential part of the doffer clothing. It was found in practice, however, that the covering strip has to be very firmly attached in the tooth rows of the clothing to ensure a clean separation of the fiber material, to prevent fibers from adhering to the cover strip and to ensure that the cover strip does not separate from the doffer. Thus, in case the covering strips are firmly attached to the doffer clothing to ensure all the above, the removal of the covering strips for the purpose of switching over to carding without web division is difficult because it requires substantial work input to disassemble and then again install the cover strips.